Creating Seamless Blends
by Wizaerd

Date Posted: 08/18/2001 - Seamless Shape Blending
When using the Blend tool, and binding the Blend to a path, it's very obvious where the starting and ending shapes are, as shown in the left hand side of this diagram. It looks tacky when we want a seamless, flowing blend like that shown in the right hand side. SO what can we do to achieve the right hand side? It's actually a lot easier than you might think.



The first thing we do is draw an oval. And we want to rotate that oval 45 degrees. I'm sure you can skip the rotating effect, but I like the slantiness of it. Put the oval in point editing mode, and select the point at the top of the oval. Right click and choose break from the context menu. If we don't break the path apart, I assume the starting and ending points are on the sides of the oval, which is part of the reason we get an irregular non-flowing blend. By breaking the oval at the top, we're specifically setting the starting and ending point for the blend.



Now draw a small rounded rectangle. The one I chose is very rounded, giving an almost pill like appearance. Duplicate it, and select Blend under the Effects menu. This will open the Blend dialog. Be sure to choose the Bind to Path option and enter an appropriate number of duplicates. For this example I chose 90, but you may have to experiment a bit to get the right look.



Your mouse cursor should change to a cross hair, with the words "Choose Path" floating around. Click anywhere on the oval, and you're blend will occur. It will create a group of your small duplicate rectangles and the oval. Un-group it,, and delete the oval as we're now done with it.

With all the rectangles selected, open up a gradient ink, one that goes from left to right. Again, for this example I chose just two colors, although a bit of experimentation may give you some neater looking objects.



Now you'll want to zoom in on the obvious starting object. You'll want to select it only, open the inks manager and click the Edit button. This will allow you to change the gradient on that one object, pulling the right hand point so the color is not so graduated.



And for the final step, keeping that singular object selected, create a directional Vector Transparency, dragging from right to left. Play with the points a bit until you get a satisfactory transparency, and the object appears to flow into the ones behind it.



Now group all your objects and render them, and you'll end up with a nearly seamless, flowing optical illusion. It won't be perfect, but it sure looks better than the default blend. With more experimentation, you may even get a perfect result.



** ADDENDUM **

Thanks to JHren for the following tip... Instead of using a transparency in the final step to merge your starting and ending object, select the first shape created in the blend (it'll be on the bottom of the stacking order) and duplicate it, which will bring it to the front. Select it and the object immediately to the left (the second topmost object) and use the Subtract Front combine method. This will improve the look of seamlessness without having to mess around with transparency.